sysdeps/s390/sysdep.h

   1 /* Assembler macros for s390.
   2    Copyright (C) 2000 Free Software Foundation, Inc.
   3    Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <sysdeps/generic/sysdep.h>
  22
  23 #ifdef  __ASSEMBLER__
  24
  25 /* Syntactic details of assembler.  */
  26
  27 #ifdef HAVE_ELF
  28
  29 /* ELF uses byte-counts for .align, most others use log2 of count of bytes.  */
  30 #define ALIGNARG(log2) 1<<log2
  31 /* For ELF we need the `.type' directive to make shared libs work right.  */
  32 #define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg;
  33 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
  34
  35 /* In ELF C symbols are asm symbols.  */
  36 #undef  NO_UNDERSCORES
  37 #define NO_UNDERSCORES
  38
  39 #else
  40
  41 #define ALIGNARG(log2) log2
  42 #define ASM_TYPE_DIRECTIVE(name,type)   /* Nothing is specified.  */
  43 #define ASM_SIZE_DIRECTIVE(name)        /* Nothing is specified.  */
  44
  45 #endif
  46
  47
  48 /* Define an entry point visible from C. */
  49 #define ENTRY(name)                                                           \
  50   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);                                   \
  51   ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)                          \
  52   .align ALIGNARG(2);                                                         \
  53   C_LABEL(name)                                                               \
  54   CALL_MCOUNT
  55
  56 #undef  END
  57 #define END(name)                                                             \
  58   ASM_SIZE_DIRECTIVE(name)                                                    \
  59
  60 /* If compiled for profiling, call `mcount' at the start of each function.  */
  61 #ifdef  PROF
  62 #ifdef PIC
  63 #define CALL_MCOUNT \
  64   lr 0,14 ; bras 14,.+12 ; .long _GLOBAL_OFFSET_TABLE_ - . ; .long 0f-. ; \
  65   lr 1,14 ; al 1,4(14) ; al 14,0(14) ; l 14,_mcount@GOT(14) ; \
  66   basr 14,14 ; lr 14,0 ; .data ; .align 4 ; 0: .long 0 ; .text ;
  67 #else
  68 #define CALL_MCOUNT \
  69   lr 0,14 ; bras 14,.+12 ; .long _mcount ; .long 0f ; \
  70   l 1,4(14) ; l 14,0(14) ; basr 14,14 ; lr 14,0 ; \
  71   .data ; .align 4 ; 0: .long 0 ; .text ;
  72 #endif
  73 #else
  74 #define CALL_MCOUNT             /* Do nothing.  */
  75 #endif
  76
  77 #ifdef  NO_UNDERSCORES
  78 /* Since C identifiers are not normally prefixed with an underscore
  79    on this system, the asm identifier `syscall_error' intrudes on the
  80    C name space.  Make sure we use an innocuous name.  */
  81 #define syscall_error   __syscall_error
  82 #define mcount          _mcount
  83 #endif
  84
  85 #define PSEUDO(name, syscall_name, args)                                      \
  86 lose: SYSCALL_PIC_SETUP                                                       \
  87   JUMPTARGET(syscall_error)                                                   \
  88   .globl syscall_error;                                                       \
  89   ENTRY (name)                                                                \
  90   DO_CALL (syscall_name, args);                                               \
  91   jm lose
  92
  93 #undef  PSEUDO_END
  94 #define PSEUDO_END(name)                                                      \
  95   END (name)
  96
  97 #ifdef PIC
  98 #define JUMPTARGET(name)  \
  99     basr %r1,0            \
 100 0:  al   %r1,1f-0b(0,%r1) \
 101     br   %r1              \
 102 1:  .long name##@PLT - 0b
 103 #define SYSCALL_PIC_SETUP             \
 104     bras  %r12,1f                     \
 105 0:  .long _GLOBAL_OFFSET_TABLE_-0b    \
 106 1:  al    %r12,0(%r12)
 107 #else
 108 #define JUMPTARGET(name)   \
 109     basr  %r1,0            \
 110 0:  al    %r1,1f-0b(0,%r1) \
 111     br    %r1              \
 112 1:  .long name - 0b
 113 #define SYSCALL_PIC_SETUP       /* Nothing.  */
 114 #endif
 115
 116 /* Local label name for asm code. */
 117 #ifndef L
 118 #define L(name)         name
 119 #endif
 120
 121 #endif  /* __ASSEMBLER__ */